Celtic’s squad against Kilmarnock offered an interesting snapshot of how the club’s late summer transfer business has developed.

Six players arrived during the final couple of days of the window as Celtic added Sam Johnstone, Oliver Sørensen, Shumaira Mheuka, Landon Emenalo, Joël van den Berg and Jordan Lotomba.

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On paper, that is a striking statistic more than two months after Celtic’s late rush of transfer activity. The circumstances surrounding each player, though, provide important context.

Johnstone has been the clearest success of the signings so far.

The goalkeeper arrived from Wolves to provide competition and has since worked his way into the side, starting Celtic’s last six matches.

He retained his place against Kilmarnock after playing against Beşiktaş on Thursday and made an important contribution almost immediately.

Johnstone produced a double save inside the opening couple of minutes as Celtic survived an early scare before going on to secure a 1-0 Premiership victory.

His situation is therefore very different from the other five late arrivals who were missing on Sunday.

Sørensen joined from Parma on a season-long loan, with Celtic holding an option to buy the Danish midfielder.

He has received opportunities without yet establishing himself as a regular starter.

Recent selections also require some context.

Sørensen missed the Falkirk match following a family bereavement before returning to the bench against Beşiktaş.

He was then left out of the squad entirely against Kilmarnock, with no public explanation given for his absence.

Mheuka was always likely to require patience.

The 19-year-old arrived on loan from Chelsea after signing a new long-term contract with the Premier League club.

Although he already had some senior experience in London, his move to Celtic represents his first prolonged spell of regular first-team football away from Chelsea.

Most of his opportunities have come from the bench.

There have already been glimpses of what he can offer. Mheuka had a late goal ruled out against St Mirren and was denied by the goalkeeper after coming on against St Johnstone.

He has also been given minutes with Celtic B as the club attempts to keep him playing regularly while he adjusts to senior football in Scotland.

Emenalo’s circumstances have been different again.

The 19-year-old defender joined from Chelsea but remained with his parent club initially as he completed his rehabilitation from injury.

He did not begin training fully with Celtic until October, leaving him several weeks behind his new teammates.

Since then, Emenalo has made substitute appearances in the Premiership while also getting competitive minutes with Celtic B.

His absence against Kilmarnock therefore has to be viewed alongside the fact he has effectively been playing catch-up since arriving in Glasgow.

Lotomba joined Celtic from Feyenoord on a deal running until the end of the season.

The Swiss international was included in Celtic’s Europa League squad but has found opportunities difficult to come by, with Colby Donovan producing a number of impressive displays at right-back.

Lotomba was handed his first Celtic start against Beşiktaş on Thursday before Donovan replaced him during the second half.

Three days later, Lotomba was not included in the Kilmarnock squad.

No explanation was provided for that absence, meaning it would be premature to read too much into one team selection.

The player perhaps attracting the most interest among those missing is Van den Berg.

The Dutch midfielder joined from PSV on a four-year contract, with Celtic holding an option for a further season.

Unlike most of the other deadline arrivals, Celtic have made a longer-term commitment to the 19-year-old.

His lack of first-team football, however, cannot simply be put down to selection.

Van den Berg suffered an ankle injury in training not long after arriving and was subsequently pictured wearing a protective boot.

The setback interrupted his first weeks at the club and prevented him from building the momentum required to push for a place.

He only returned to full first-team training towards the end of October.

Van den Berg then played 72 minutes for Celtic B against Ross County at the beginning of November as he continued building his match fitness.

He has yet to make his competitive first-team debut and was not included in Celtic’s Europa League squad, although he has previously been named among the substitutes domestically.

That makes the coming weeks particularly interesting.

Van den Berg arrived as a young midfielder with development still ahead of him rather than someone guaranteed to walk immediately into Celtic’s starting XI. His injury has made that process slower than either the player or club would have wanted.

Sunday’s team sheet should not, on its own, be taken as proof that Celtic’s late summer recruitment has failed.

Johnstone is already having a meaningful impact, while several of the other additions arrived either as development players or to increase competition within O’Neill’s squad.

Injury and personal circumstances have also affected the picture.

What the Kilmarnock selection does show is that Celtic are still waiting to see the full benefit of several players signed during those frantic final days of the window.

The international break now gives O’Neill another opportunity to assess the group before Celtic enter a demanding run of domestic and European fixtures.

For Van den Berg in particular, after finally getting back onto the pitch following his ankle injury, the next few weeks offer his first real chance to make a sustained push towards O’Neill’s first-team plans.

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